git-upstream-diff(1)
====================

NAME
----
git-upstream-diff -
include::_git-upstream-diff_desc.helper.txt[]

SYNOPSIS
--------
[verse]
'git upstream-diff' [--wordwise] [--branch branch] [<extra args for git-diff>*]

DESCRIPTION
-----------

Shows a diff between a branch and its upstream. If the --branch option is
omitted or "HEAD", the tool shows the diff for the current branch. Any
additional arguments are passed through to the underlying git-diff command. This
is 'roughly' the same as:

----
git diff --patience -C -C branch@{upstream}  <1> <2>
----
<1> `-C -C` detects file copies/renames
<2> `--patience` uses the patience-diff algorithm, which tends to produce nicer
  diffs in many cases.

The difference is that `branch@{upstream}` is actually the tagged merge base of
your branch (See linkgit:git-rebase-update[1]). This means that if your upstream
branch was rebased, but you haven't yet rebased the current branch on top of it,
you'll still see an accurate diff compared to just diffing against
`@{upstream}`.

The `--wordwise` option also allows `git-diff` to do word-by-word comparison
in a semi-intelligent way. However, sometimes it can produce surprising results,
so it is disabled by default.

Since any additional options are passed through to git-diff unchanged, you can
use this as a general replacement for `git diff` for things like:

----
$ # See what changed in a file on the current branch
$ git upstream-diff some/file.py
...

$ # Omit deleted files from the diff
$ git upstream-diff --diff-filter d
...

$ # etc.
----


OPTIONS
-------

--wordwise::
  Print a colorized word-wise diff instead of a line-wise diff.

--branch branch::
  Show a diff between the specified branch and its upstream, instead of using
  the current branch.

<extra args for git-diff>::
  Extra arguments are included in the invocation of linkgit:git-diff[1]. These
  can be anything that `git-diff` normally takes.
+
--
`--stat`;;
  This is particularly useful to show 'which' files have been changed in
  comparison to the upstream branch.
`--staged`;;
  Diff against the staged (cached) changes, instead of against the working
  directory. This is 'substantially' faster on large repos, but doesn't take
  into account unstaged changes (i.e. changes in your working copy which you
  haven't staged with `git add`).
`-- <filename patterns>*`;;
  Restrict the diff to only show the diff for given files compared to the
  upstream.
--


CONFIGURATION VARIABLES
-----------------------

depot-tools.upstream-diff.default-args
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

A list-configuration variable. Each instance of this config variable will be
prepended to all invocations of `git upstream-diff`, as if you had passed them
on the command line.

include::_aliases.txt[]

----
[alias]
  udiff = upstream-diff
----

SEE ALSO
--------
linkgit:git-rebase-update[1]

include::_footer.txt[]

// vim: ft=asciidoc:
